Manufacturing method of silicon single crystal

Abstract

In appropriate setting of magnetic field applied to a molten silicon 12 stored in a cylindrical quartz crucible 11, the maximum value B 0 of magnetic flux density on a vertical symmetric axis 17 as a cylindrical axis of the quartz crucible 11 in horizontal magnetic field generated by a pair of exciting coils 13 and 14 calls B 0 . On circle at which horizontally symmetric plane 18 traversing and perpendicular to a vertically symmetric axis 17 becoming magnetic flux B 0 crosses an inner diameter of the quartz crucible 11, the minimum value of magnetic flux density calls B min , and the maximum value of magnetic flux density calls B max . Those magnetic flux densities B 0 , B min and B max are adjusted to be given ranges, and upward flow and temperature of a molten silicon 12 at the lower part of a solid-liquid interface 15 a are appropriately controlled.

1 . A manufacturing method of silicon single crystal, comprising:
 pulling out a silicon single crystal from melt silicon stored in a cylindrical crucible by Czochralski method while applying horizontal magnetic field satisfying formulas of
   2000/( Φcry/Φcru ) 1/2 −2000 ≦B   0 ≦2000/(Φ cry/Φcru ) 1/2 +2000 and 
   0.8B 0≦B   min  or 0.6B max ≦B min   
   wherein B 0  [gauss] is a maximum value of a magnetic flux density on an cylindrical axis of the crucible,   B min  [gauss] is a minimum value of the magnetic flux density on a circle where an inner diameter of the crucible intersects with a horizontal plane which crosses a point of which magnetic flux density is B 0  and is perpendicular to the cylindrical axis of the crucible,   B max  [gauss] is a maximum value of the magnetic flux density on the circle,   Φ cry  is a diameter of a straight body part of the silicon single crystal,   Φ cru  is an inner diameter of the crucible, and   the horizontal magnetic field is applied by a pair of exciting coils disposed on both side portions of the crucible.   
     
     
         2 . The manufacturing method of the silicon single crystal as set forth in  claim 1 ,
 wherein B 0  satisfying
       2000   /(Φ cry/Φcru ) 1/2 −1000≦ B   0 ≦2000/(Φ cry/Φcru ) 1/2 +1000 . 
   
     
     
         3 . The manufacturing method of the silicon single crystal as set forth in  claim 1 , wherein the exciting coil is a saddle-shaped coil. 
     
     
         4 . The manufacturing method of the silicon single crystal as set forth in  claim 1 , wherein a ratio of Φ cry /Φ cru  is set larger as a required oxygen concentration in the silicon single crystal is higher. 
     
     
         5 . A manufacturing method of a silicon single crystal comprising:
 pulling out a silicon single crystal from melt silicon stored in a cylindrical crucible by Czochralski method while applying horizontal magnetic field satisfying formulas of
   1500/(Φ cry/Φcru )−2000≦ B   0 ≦1500/(Φ cry/Φcru )+2000 and 
   B min ≦0.9B 0  or B min ≦0.65B max    
   wherein B 0  [gauss] is a maximum value of a magnetic flux density on an cylindrical axis of the crucible,   B min  [gauss] is a minimum value of the magnetic flux density on a circle where an inner diameter of the crucible intersects with a horizontal plane which crosses a point of which magnetic flux density is B 0  and is perpendicular to the cylindrical axis of the crucible,   B max  [gauss] is a maximum value of the magnetic flux density on the circle,   Φcry is a diameter of a straight body part of the silicon single crystal,   Φcru is an inner diameter of the crucible, and   the horizontal magnetic field is applied by a pair of exciting coils disposed on both side portions of the crucible.   
     
     
         6 . The manufacturing method of the silicon single crystal as set forth in  claim 5 ,
 wherein B 0  satisfying
   1500( Φcry/Φcru )−1000 ≦B   0 ≦1500/(Φ cry/Φcru )+1000. 
   
     
     
         7 . The manufacturing method of the silicon single crystal as set forth in  claim 5 , wherein the exciting coil is a circular coil. 
     
     
         8 . The manufacturing method of the silicon single crystal as set forth in  claim 5 , wherein a ratio of Φ cry /Φ cru  is set larger as a required oxygen concentration in the silicon single crystal is higher.